Jacking A Car Up

[jims-terrano]

Just been watching a youtube video by University Motors that specialise in MG's. The bloke is well respected in MG circles and he's done loads of videos but theres one video that I just can't get at all.
I've been taught from very early days with my father that when jacking a car up you always have hand brake on and in gear with chocks for good measure. This chap is saying none of that. He recommends when using a trolley jack you have hand brake off, not in gear and no chocks. This allows the car and jack to move so that the car doesn't fall from the jack.
He does recommend if not stipulate that you use "jack stands" or as we call them axle stands.

It just doesn't seem right allowing the car to move as you jack it up.

 

[Lazy-Ferret]

Well it would not work on my drive, as while it is not a lot, it still has enough of a slope that the trolley jack will roll off down the drive once the rear wheels with the hand brake on, are lifted. I know, as I forget to put the chock back in front of the wheels one time...

The other thing is, if you then want to lower it down onto axle stands, you have no idea whether the car or jack are going to move, making lining things up more difficult.

I think I will stick with safety first, and use chocks, and stands.

Having said that, when the tyre guys do all 4, they just lift the car on 4 trolley jacks, with no chocks.

 

[solarman216]

I go with that if you are on level ground, the small wheels of a trolley jack even in a workshop with smooth concrete floor will lock on a very small object, but if the vehicle can move then there is no tendency for the vehicle and jack to fight for position, but I am talking here of the more commercial high lift jacks found in typical workshops, means that if jack stays still the motor may move 4 or 5 inches towards the jack, but have to stress this only applies on level ground, all other circumstances chock the wheels and watch the jack, if is shows signs of not rolling then there is a danger that it could slide off, Rick

 

[macabethiel]

Car Jacking right & wrongs

Just been watching a youtube video by University Motors that specialise in MG's. The bloke is well respected in MG circles and he's done loads of videos but theres one video that I just can't get at all.
I've been taught from very early days with my father that when jacking a car up you always have hand brake on and in gear with chocks for good measure. This chap is saying none of that. He recommends when using a trolley jack you have hand brake off, not in gear and no chocks. This allows the car and jack to move so that the car doesn't fall from the jack.
He does recommend if not stipulate that you use "jack stands" or as we call them axle stands.

It just doesn't seem right allowing the car to move as you jack it up.

When I am jacking up to say change the front brakes I have the car in neutral handbrake off but I put a brick an inch or so away from the rear wheels in front and behind. When at required height place axle stands and lower onto stands. Then push bricks or wooden chocks up against the rear tyres. Do the job then lower usually forgetting to move bricks so have to drive over them as they are stuck fast under the tyres at one end or the other.

 

[rustic]

Most trolley jacks do not travel vertically, they tend to travel in an arc, to help compensate, the trolley jack has wheels so the jack can follow the car, but debris or roughness under the wheels doesn't guarantee it.

You also have to consider the angle of the jack to the car, if at 45 degree, it is trying to pull the car backwards towards the jack, so chocking the wheels could topple the jack, or encourage the jack to slide on the jacking point.

If I jack the mav by the rear diff, the car is free to move on a flat and level concrete surface.When high enough, I then start chocking wheels, adding axle stands etc.

Due to levels, firmness of ground, type of jack and what task you are performing need to be risk assessed every time. Every jacking operation has a degree of risk, if in doubt... STOP re assess, double up on supports, if you have unused ramps, or even a spare wheel, place those under the chassis with a block of wood as a catch all, just in case.

What do you call a man with a car on his head? Jack.
What do you call a man with a 4x4 on his head? Dead

Uncle Rustic